1. Field of the Invention
This invention relates to a method for fixing on a workpiece a stud possessing a fitting base at one end of the shank thereof by securing the fitting base on the workpiece by the use of a hotmelt adhesive agent.
2. Description of Prior Art
For the fitting base of a stud to be secured on a metal plate with a hotmelt adhesive agent, it is necessary to tack the fitting base to the metal plate with the aid of the hotmelt adhesive agent, fuse or activate the hotmelt adhesive agent as by placing the stud so tacked to the metal plate in an oven, remove the stud and the metal plate from the oven, and leave the molten hotmelt adhesive agent to cool and cure. When the workpiece on which the stud is fixed happens to be a wooden panel or a board of hardened aggregate of fibers, for example, the procedure just described cannot be adopted because the workpiece may catch fire in the oven.
It has been found that when a plastic stud set in place with the shank thereof fastened to the chuck of a rotary tool and the fitting base thereof pressed against a workpiece is rotated at a fairly high speed, the opposed faces of the workpiece and the fitting base generate heat because of friction and, depending on the material of the workpiece, the opposed faces of both the workpiece and the fitting base or only the face of the fitting base held in contact with the face of the workpiece is melted sufficiently to cause fusion of the workpiece and the fitting base. A method for direct fixation of the stud on the workpiece by the use of the principle described above has been proposed (Japanese Patent Application No. SHO 58(1983)-135712).